Contents

Route

The line begins at South Hills Village in Upper St. Clair, and runs north to Washington Junction through Bethel Park, providing a transfer to the 47L Library line, which runs via Overbrook. The 42S continues north through Castle Shannon and Mount Lebanon, then through the Mount Lebanon Rail Tunnel underneath Washington Rd./West Liberty Ave (aka Truck U.S. Route 19) into Dormont at the other end. The first station coming out of the tunnel northbound is Dormont Junction, then line proceeds through this suburb, crossing many streets via grade crossings. The line then arrives at Potomac, where it begins travelling through street trackage about a quarter mile down the tracks, crossing into the neighborhood of Beechview in the city of Pittsburgh near the Neeld Avenue stop.

Before the Mt. Lebanon Rail Tunnel, the old streetcars ran with car traffic on Washington Rd. between Alfred St. in Mt. Lebanon and the intersection of McFarland Rd. and Raleigh Ave. (where Washington Rd. becomes West Liberty Ave.) in Dormont.